Preparing for a fall Half Marathon during the hot and humid Summer months (i.e. the Rock 'n' Roll Philadelphia Half Marathon - part of the annual Philadelphia Running Festival - is a great race)? If so, there are several things you can do to minimize the hazards of running in the heat and maximize both your enjoyment and performance (during training and the race).
Listed below are several tips and techniques to help you beat the heat:
You need to acclimate to the heat in a safe and gradual manner, not haphazardly. For the first two weeks of hot weather, do not do speed sessions and keep your midday running bouts to 30 easy minutes at most. (You can go longer on cool mornings or evenings.) Slow your pace and reduce your intensity while you are getting acclimated to hotter tempatures. As your body adjusts, you will gradually be able to pick up the pace. In 10 days to two weeks, you should be 'heat resistant' and fully acclimated.
Begin your training session adequately hydrated. Hydrate on an ongoing basis and not just when you are exercising. Consume water throughout the day and make it a lifestyle habit. Drink while training and don't wait until you 'feel' thirsty. By that time you are probably already in an underhydration state and your performance will degrade rapidly. Also, make hydration a part of your post-run recovery. Incorporate an electrolyte-balance sports drink (i.e. Gatorade, Powerade, etc.) into your hydration plan especially on one-hour plus runs and as part of your post run recovery.
For workouts shorter than 45 minutes, water works just fine. For longer runs however, research suggests consuming about a cup of sports drink every 15 to 20 minutes to fuel your muscles and aid in maintaining electrolyte levels.
Run at cooler times of the day. You could get your training in early morning before sunrise or after sunset. Humidity is higher in the morning but air quality is better. If you can run early, you've got your training run out of the way right off the bat and it will more likely be close to the time of your actual race.
Seek out shady routes for relief from the sun. Dress in light-colored, synthetic clothing (to reflect the sun's rays, wick and dry quickly), that fits loose enough to promote airflow. Moving air helps to evaporate sweat and can maintain body tempature.
Know where your water stops are, either by plotting your runs in areas that have water fountains or by stashing bottles at strategic points along your route ahead of time. Also get in touch with local running clubs and training groups to find out where they might put out Water and/or sports drinks so you can share.
Wearing light-colored running tops and shorts made of technical fabrics will keep you cool and allow moisture to evaporate more quickly. Staying dry will also help prevent chafing. Clothing made of polyester, Lycra, Nylon, CoolMax, and Dry-Fit are some examples of technical fabrics.
Make use of one of the many lubricant products on the market (BodyGlide, Vaseline, etc.) to keep chafing to a minimum.
In severe heat, be sure to run with a buddy. That way you can keep tabs on each other. Sometimes it's hard to tell if you're starting to suffer the effects of the heat, but a buddy may be able to spot the signs before it's too late.
Let your family and friends know your running route. If you're gone too long, they'll know where to look for you. If you run on rural greenways or trails, you may even want to pack your cell phone. Don't change your running route plans at the last minute without letting someone know. It's better to be safe than sorry.